A classified National Reconnaissance Office (NRO) satellite launched Saturday night from Cape Canaveral AFB, Fla., on a Delta IV heavy rocket provided by United Launch Alliance.

ULA is a joint venture of Boeing [BA] and Lockheed Martin [LMT], and the Delta IV is a historically Boeing lifter. It was the first time an NRO payload was orbited by a Delta IV.

The effort also involved Alliant Techsystems [ATK], which designed and produced the nozzle for the Pratt & Whitney Rocketdyne-built RS-68 engine as well as the nozzle’s thermal protection material, which is capable of shielding it from the extreme heat of launch when external temperatures can exceed 4,000 degrees F.

Pratt is a unit of United Technologies [UTX].

The Delta IV RS-68 is the largest hydrogen-fueled engine in the world, utilizing an ATK nozzle that is the first of its kind in a liquid booster engine. The nozzle is manufactured at the ATK Promontory, Utah, facility.

ATK also supplied 12 key composite structures for the Delta IV heavy launch vehicle: the interstage that provides the interface between the Common Booster Core (CBC) and the cryogenic second stage, two nose cones for the port and starboard strap-on CBC’s, three centerbodies that integrate the liquid oxygen (LO2) and liquid hydrogen (LH2) tanks, three thermal shields that protect the RS-68 engines during ignition and flight, and three LO2 skirts.